The costs for shipping a package vary depending on the size and weight of the package. For example, a large box that is very heavy may cost more to ship than a small box that is very light. In addition to size and weight, the distance the package has to travel and how fast the package needs to get to its destination can also effect the shipping cost. For example, shipping a letter overnight from across the country may be more expensive than shipping a small box to a neighboring town with no time constraints.